1
|
Ma X, Liu H, Jia Q, Zheng Y, Li W, Chang M, Fu H, Zhu H. Diverse roles of glucocorticoids in the ruminant mammary gland: modulation of mammary growth, milk production, and mastitis. Stress 2023; 26:2252938. [PMID: 37632459 DOI: 10.1080/10253890.2023.2252938] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Accepted: 08/23/2023] [Indexed: 08/28/2023] Open
Abstract
As endocrine hormones, glucocorticoids (GCs) play a pivotal role in numerous physiological processes, including mammary growth and lactation, circulatory metabolism, and responses to external stimuli. In the dairy industry, milk production from cows or goats is important for newborns and economic benefits. However, the milk yields from ruminant animals are always affected by the extent of mammary development, mammary disease, stress, or changes in metabolism. Thus, it is necessary to clarify how GCs changes in ruminants affect ruminant mammary gland function and mammary disease. This review summarizes the findings identifying that GCs modulate mammary gland development before lactation, but the stress-induced excessive release of GCs leads to milk production loss. In addition, the manner of GCs release may change under different concentrations of metabolites or during mastitis or inflammatory challenge. Nevertheless, exogenous GCs administration to animals may alleviate the clinical symptoms of mastitis. This review demonstrates that GCs offer a fascinating contribution to both physiologic and pathogenic conditions of the mammary gland in ruminant animals. Characterizing and understanding these changes or functions of endogenous and exogenous GCs in animals will be crucial for developing more endocrine regulators and therapies for improving milk production in ruminants.
Collapse
Affiliation(s)
- Xiaoyue Ma
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
| | - Hanling Liu
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
| | - Qianqian Jia
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
| | - Yumiao Zheng
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
| | - Wentao Li
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
| | - Mengyu Chang
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
| | - Haixia Fu
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
| | - Hongmei Zhu
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
| |
Collapse
|
2
|
Effect of experimental stress and cortisol release induced by ACTH administration on expression of key genes related to milk synthesis and apoptosis during mammary involution of Saanen goats. J DAIRY RES 2022; 89:404-409. [PMID: 36398762 DOI: 10.1017/s0022029922000735] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
This research paper addresses the hypothesis that stress, induced by ACTH administration and cortisol release increases somatic cell count (SCC) in mammary secretion, and improves the effectiveness of dry off in goats. We report indicators of milk synthesis and mammary gland involution during dry off. Thirty Saanen goats were subjected to abrupt dry off and treatments: (1) ACTH administration (ACTH) or (2) placebo (Control) on days 1, 3, 6, 9, 12, 15, 30, and 60 of dry off. The expression of target genes in mammary tissue that are related to milk synthesis and cell survival such as insulin-like growth factor 1 receptor (IGF1R), phosphatidylinositol-3-kinase (PIK3CA), protein kinase B (AKT1) and mechanistic target of rapamycin (MTOR), casein (CSN2), lactalbumin (LALBA) and lactoferrin (LF) were evaluated, and plasma cortisol concentration, SCC, leucocyte count, and microbiological analyses in milk and mammary secretions were assessed. ACTH significantly downregulated the expression of IGF1R and upregulated the expression of PIK3CA in mammary tissue, increased lactoferrin concentration and SCC, and changed immune cell levels in mammary secretions compared to Control. Furthermore, ACTH administration increased the percentage of dry goats compared to the Control (73 vs. 46%, respectively). We conclude that the effect of stress via ACTH administration and cortisol release accelerated mammary involution during the early dry-off period.
Collapse
|
3
|
Bomfim GF, Merighe GKF, de Oliveira SA, Negrao JA. Acute and chronic effects of cortisol on milk yield, the expression of key receptors, and apoptosis of mammary epithelial cells in Saanen goats. J Dairy Sci 2021; 105:818-830. [PMID: 34756435 DOI: 10.3168/jds.2021-20364] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2021] [Accepted: 09/08/2021] [Indexed: 11/19/2022]
Abstract
Cortisol (CORT) induces mammary development in late gestation and is fundamental to the differentiation of mammary epithelial cells and lactogenesis. The objective of this study was to investigate the relationship between CORT, insulin, prolactin, growth hormone, and insulin-like growth factor-1 in milk as well as the effect of CORT on the expression of receptors of insulin (INSR), prolactin (PRLR), growth hormone (GHR); we also studied the insulin-like growth factor-1 (IGF1R), glucocorticoid (NR3C1), mineralocorticoid (NR3C2), B-cell lymphoma 2 (BCL2), BCL-2-like protein X (BAX) genes, and the apoptosis rate of mammary epithelial cells of lactating Saanen goats in vivo and in vitro. The following experiments were conducted: (1) comparing hormone release in milk and blood after ACTH or a placebo administration; (2) evaluating the effect of acute CORT increases in mammary gland expression and milk yield in vivo; and (3) evaluating the effect of a chronic increase in CORT concentration in epithelial mammary cell apoptosis in vitro. In vivo, ACTH administration significantly increased CORT release but did not affect insulin, prolactin, growth hormone, and insulin-like growth factor-1 release in plasma and milk versus placebo. The results show also that a low CORT release after ACTH administration increased the expression of GHR and PRLR genes in the mammary tissue. Indeed, CORT release significantly increased the milk yield from goats subjected to ACTH versus goats subjected to the placebo. However, a higher amount of CORT added in vitro upregulated the NR3C1, GHR, PRLR, and BAX genes and downregulated the IGF1R and INSR genes, which could negatively modulate the apoptosis of mammary epithelial cells. Finally, the effect of CORT in vivo after ACTH administration demonstrated the increased expression of the PRLR and GHR genes, which may improve epithelial cell responsiveness and be associated with the positive effect of CORT observed on milk yield at mid-end lactation.
Collapse
Affiliation(s)
- G F Bomfim
- Department of Basic Sciences, Faculty of Animal Science and Food Engineering (FZEA), University of Sao Paulo (USP), Pirassununga, SP, 13635-900 Brazil
| | - G K F Merighe
- Department of Basic Sciences, Faculty of Animal Science and Food Engineering (FZEA), University of Sao Paulo (USP), Pirassununga, SP, 13635-900 Brazil
| | - S A de Oliveira
- Department of Basic Sciences, Faculty of Animal Science and Food Engineering (FZEA), University of Sao Paulo (USP), Pirassununga, SP, 13635-900 Brazil
| | - J A Negrao
- Department of Basic Sciences, Faculty of Animal Science and Food Engineering (FZEA), University of Sao Paulo (USP), Pirassununga, SP, 13635-900 Brazil.
| |
Collapse
|
4
|
Nagy D, Gillis CMC, Davies K, Fowden AL, Rees P, Wills JW, Hughes K. Developing ovine mammary terminal duct lobular units have a dynamic mucosal and stromal immune microenvironment. Commun Biol 2021; 4:993. [PMID: 34417554 PMCID: PMC8379191 DOI: 10.1038/s42003-021-02502-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Accepted: 07/27/2021] [Indexed: 11/29/2022] Open
Abstract
The human breast and ovine mammary gland undergo striking levels of postnatal development, leading to formation of terminal duct lobular units (TDLUs). Here we interrogate aspects of sheep TDLU growth as a model of breast development and to increase understanding of ovine mammogenesis. The distributions of epithelial nuclear Ki67 positivity differ significantly between younger and older lambs. Ki67 expression is polarised to the leading edge of the developing TDLUs. Intraepithelial ductal macrophages exhibit periodicity and considerably increased density in lambs approaching puberty. Stromal macrophages are more abundant centrally than peripherally. Intraepithelial T lymphocytes are more numerous in older lambs. Stromal hotspots of Ki67 expression colocalize with immune cell aggregates that exhibit distinct organisation consistent with tertiary lymphoid structures. The lamb mammary gland thus exhibits a dynamic mucosal and stromal immune microenvironment and constitutes a valuable model system that provides new insights into postnatal breast development.
Collapse
Affiliation(s)
- Dorottya Nagy
- Department of Veterinary Medicine, University of Cambridge, Cambridge, UK
- Equine Clinic, Department of Companion Animals and Equids, Faculty of Veterinary Medicine, University of Liège, Liège, Belgium
| | - Clare M C Gillis
- Department of Veterinary Medicine, University of Cambridge, Cambridge, UK
| | - Katie Davies
- Department of Physiology, Development, and Neuroscience, University of Cambridge, Cambridge, UK
| | - Abigail L Fowden
- Department of Physiology, Development, and Neuroscience, University of Cambridge, Cambridge, UK
| | - Paul Rees
- College of Engineering, Swansea University, Fabian Way, Crymlyn Burrows, Swansea, UK
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - John W Wills
- Department of Veterinary Medicine, University of Cambridge, Cambridge, UK.
| | - Katherine Hughes
- Department of Veterinary Medicine, University of Cambridge, Cambridge, UK.
| |
Collapse
|
5
|
Sadovnikova A, Garcia SC, Hovey RC. A Comparative Review of the Extrinsic and Intrinsic Factors Regulating Lactose Synthesis. J Mammary Gland Biol Neoplasia 2021; 26:197-215. [PMID: 34125363 PMCID: PMC8236052 DOI: 10.1007/s10911-021-09491-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Accepted: 05/20/2021] [Indexed: 12/31/2022] Open
Abstract
Milk is critical for the survival of all mammalian offspring, where its production by a mammary gland is also positively associated with its lactose concentration. A clearer understanding of the factors that regulate lactose synthesis stands to direct strategies for improving neonatal health while also highlighting opportunities to manipulate and improve milk production and composition. In this review we draw a cross-species comparison of the extra- and intramammary factors that regulate lactose synthesis, with a special focus on humans, dairy animals, and rodents. We outline the various factors known to influence lactose synthesis including diet, hormones, and substrate supply, as well as the intracellular molecular and genetic mechanisms. We also discuss the strengths and limitations of various in vivo and in vitro systems for the study of lactose synthesis, which remains an important research gap.
Collapse
Affiliation(s)
- Anna Sadovnikova
- Graduate Group in Nutritional Biology, Physician Scientist Training Program, University of California, Davis, CA, United States.
- Department of Animal Science, University of California, Davis, CA, United States.
| | - Sergio C Garcia
- School of Life and Environmental Sciences, University of Sydney, Sydney, Australia
| | - Russell C Hovey
- Department of Animal Science, University of California, Davis, CA, United States
| |
Collapse
|
6
|
Zamuner F, Cameron AWN, Carpenter EK, Leury BJ, DiGiacomo K. Endocrine and metabolic responses to glucose, insulin, and adrenocorticotropin infusions in early-lactation dairy goats of high and low milk yield. J Dairy Sci 2020; 103:12045-12058. [PMID: 32981734 DOI: 10.3168/jds.2020-18625] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Accepted: 07/17/2020] [Indexed: 01/16/2023]
Abstract
This experiment aimed to examine endocrine and metabolic responses to glucose, insulin, and adrenocorticotropin (ACTH) infusions in early-lactation dairy goats of different levels of milk production (LMP). Goats were grouped as either high (HY; 4.0 L/d, n = 13) or low milk yield (LY; 2.4 L/d, n = 13). Individual milk yield (L/d) and dry matter intake (DMI; kg/d) were measured daily. Concentration (mM) of glucose, fatty acids, and β-hydroxybutyrate, percent of milk fat and protein, body weight (BW; kg), and body condition score (BCS) were assessed weekly (from 2-6 wk postpartum). An intravenous glucose tolerance test (IVGTT), an insulin tolerance test (ITT), and an ACTH stimulation test were carried out at 43, 44, and 45 ± 0.7 d in milk, respectively. The HY goats had greater milk yield (+67%), energy-corrected milk (ECM; +70%), DMI (+28%), ratio of ECM output to metabolic BW (+67%), and feed efficiency (+25%), but lesser BCS than LY goats (2.4 vs. 2.6). The DMI (% of BW) was moderately correlated with ECM (r = 0.70) and negatively correlated with BCS (r = -0.57). At the time of the IVGTT, HY goats had lesser basal insulin and glucose than LY goats. However, results from IVGTT and ITT indicate that the sensitivity of peripheral tissues to insulin was unaffected by LMP. Compared with LY, HY goats had lesser insulin secretion (-52%) and greater insulin clearance rate (+47%) after glucose infusion. The ITT and ACTH stimulation test results show that both the growth hormone response to insulin and the cortisol response to ACTH were unaffected by LMP. Also, basal plasma concentrations of GH and cortisol were not correlated with glucose and fatty acids concentrations or any performance traits. Collectively, our results suggest that differences between HY and LY goats, concerning milk yield and feed efficiency, were probably more closely related to differences in insulin secretion and clearance than to differences in peripheral tissue responsiveness to the effects of catabolic and anabolic hormones.
Collapse
Affiliation(s)
- F Zamuner
- Faculty of Veterinary and Agricultural Sciences, the University of Melbourne, Parkville, Victoria 3010, Australia.
| | - A W N Cameron
- Meredith Dairy Pty Ltd., 106 Cameron Rd, Meredith, Victoria 3333, Australia
| | - E K Carpenter
- Faculty of Veterinary and Agricultural Sciences, the University of Melbourne, Parkville, Victoria 3010, Australia; Meredith Dairy Pty Ltd., 106 Cameron Rd, Meredith, Victoria 3333, Australia
| | - B J Leury
- Faculty of Veterinary and Agricultural Sciences, the University of Melbourne, Parkville, Victoria 3010, Australia
| | - K DiGiacomo
- Faculty of Veterinary and Agricultural Sciences, the University of Melbourne, Parkville, Victoria 3010, Australia
| |
Collapse
|
7
|
Hooper H, Silva PDS, de Oliveira S, Meringhe G, Lacasse P, Negrão J. Effect of heat stress in late gestation on subsequent lactation performance and mammary cell gene expression of Saanen goats. J Dairy Sci 2020; 103:1982-1992. [DOI: 10.3168/jds.2019-16734] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2019] [Accepted: 10/07/2019] [Indexed: 12/19/2022]
|
8
|
Dong J, Li J, Li J, Cui L, Meng X, Qu Y, Wang H. The proliferative effect of cortisol on bovine endometrial epithelial cells. Reprod Biol Endocrinol 2019; 17:97. [PMID: 31757215 PMCID: PMC6873581 DOI: 10.1186/s12958-019-0544-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/22/2019] [Accepted: 11/13/2019] [Indexed: 01/28/2023] Open
Abstract
BACKGROUND Bovine endometrial epithelial cells (BEECs) undergo regular regeneration after calving. Elevated cortisol concentrations have been reported in postpartum cattle due to various stresses. However, the effects of the physiological level of cortisol on proliferation in BEECs have not been reported. The aim of this study was to investigate whether cortisol can influence the proliferation properties of BEECs and to clarify the possible underlying mechanism. METHODS BEECs were treated with different concentrations of cortisol (5, 15 and 30 ng/mL). The mRNA expression of various growth factors was detected by quantitative reverse transcription-polymerase chain reaction (qPCR), progression of the cell cycle in BEECs was measured using flow cytometric analysis, and the activation of the Wnt/β-catenin and phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) signaling pathways was detected with Western blot and immunofluorescence. RESULTS Cortisol treatment resulted in upregulated mRNA levels of vascular endothelial growth factor (VEGF) and connective tissue growth factor (CTGF); however, it had no influence on transforming growth factor-beta1 (TGF-β1). Cortisol (15 ng/mL) accelerated the cell cycle transition from the G0/G1 to the S phase. Cortisol upregulated the expression of β-catenin, c-Myc, and cyclinD1 and promoted the phosphorylation of PI3K and AKT. CONCLUSIONS These results demonstrated that cortisol may promote proliferation in BEECs by increasing the expression of some growth factors and activating the Wnt/β-catenin and PI3K/AKT signaling pathways.
Collapse
Affiliation(s)
- Junsheng Dong
- grid.268415.cCollege of Veterinary Medicine, Yangzhou University, Yangzhou, 225009 Jiangsu China
- Jiangsu Co-innovation Center for the Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, 225009 Jiangsu China
| | - Jun Li
- grid.268415.cCollege of Veterinary Medicine, Yangzhou University, Yangzhou, 225009 Jiangsu China
- Jiangsu Co-innovation Center for the Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, 225009 Jiangsu China
| | - Jianji Li
- grid.268415.cCollege of Veterinary Medicine, Yangzhou University, Yangzhou, 225009 Jiangsu China
- Jiangsu Co-innovation Center for the Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, 225009 Jiangsu China
| | - Luying Cui
- grid.268415.cCollege of Veterinary Medicine, Yangzhou University, Yangzhou, 225009 Jiangsu China
- Jiangsu Co-innovation Center for the Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, 225009 Jiangsu China
| | - Xia Meng
- grid.268415.cCollege of Veterinary Medicine, Yangzhou University, Yangzhou, 225009 Jiangsu China
- Jiangsu Co-innovation Center for the Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, 225009 Jiangsu China
| | - Yang Qu
- grid.268415.cCollege of Veterinary Medicine, Yangzhou University, Yangzhou, 225009 Jiangsu China
- Jiangsu Co-innovation Center for the Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, 225009 Jiangsu China
| | - Heng Wang
- grid.268415.cCollege of Veterinary Medicine, Yangzhou University, Yangzhou, 225009 Jiangsu China
- Jiangsu Co-innovation Center for the Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, 225009 Jiangsu China
| |
Collapse
|
9
|
Zhang X, Wu J, Han X, Tan Z, Jiao J. Effects of rumen-protected glucose on ileal microbiota and genes involved in ileal epithelial metabolism and immune homeostasis in transition dairy cows. Anim Feed Sci Technol 2019. [DOI: 10.1016/j.anifeedsci.2019.06.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
|
10
|
Peng Y, Wang Y, Wang R, Geng L, Ma R, Zhang C, Liu Z, Gong Y, Li J, Li X. Exploring differentially expressed genes associated with coat color in goat skin using RNA-seq. CANADIAN JOURNAL OF ANIMAL SCIENCE 2019. [DOI: 10.1139/cjas-2018-0026] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Fur color in domestic goats is an important, genetically determined characteristic that is associated with economic value. This study was designed to perform a comprehensive expression profiling of genes expressed in the skin tissues from Laiwu Black goat and Lubei White goat. Comparisons of black and white goat skin transcriptomes revealed 102 differentially expressed genes (DEGs), of which 38 were upregulated and 64 downregulated in black skin compared with white skin. Among the DEGs, we identified six genes involved in pigmentation, including agouti signaling protein (ASIP), CAMP responsive element binding protein 3-like 1 (CREB3L1), dopachrome tautomerase (DCT), premelanosome protein (PMEL), transient receptor potential cation channel subfamily M member 1 (TRPM1), and tyrosinase-related protein 1 (TYRP1). Notably, there were no significant differences in the expression of melanocortin 1 receptor, microphthalmia-associated transcription factor, tyrosinase, and KIT proto-oncogene receptor tyrosine kinase between the black and white skin samples, whereas ASIP expression was detected only in white skin. PMEL, TRPM1, TYRP1, and DCT showed higher expression in black goat skin, but ASIP and CREB3L1 had higher expression in white goat skin. Quantitative polymerase chain reaction results for PMEL, TRPM1, DCT, TYRP1, and CREB3L1 expression were consistent with those for RNA-seq. These results will expand our understanding of the complex molecular mechanisms of skin physiology and melanogenesis in goats, and provide a foundation for future studies.
Collapse
Affiliation(s)
- Yongdong Peng
- College of Animal Science and Technology, Hebei Normal University of Science and Technology, Qinhuangdao, Hebei 066004, People’s Republic of China
| | - Yaqi Wang
- College of Animal Science and Technology, Hebei Normal University of Science and Technology, Qinhuangdao, Hebei 066004, People’s Republic of China
| | - Ruining Wang
- College of Animal Science and Technology, Hebei Normal University of Science and Technology, Qinhuangdao, Hebei 066004, People’s Republic of China
| | - Liying Geng
- College of Animal Science and Technology, Agricultural University of Hebei Province, Baoding, Hebei 071001, People’s Republic of China
| | - Ruxue Ma
- College of Animal Science and Technology, Hebei Normal University of Science and Technology, Qinhuangdao, Hebei 066004, People’s Republic of China
| | - Chuansheng Zhang
- College of Animal Science and Technology, Hebei Normal University of Science and Technology, Qinhuangdao, Hebei 066004, People’s Republic of China
| | - Zhengzhu Liu
- College of Animal Science and Technology, Hebei Normal University of Science and Technology, Qinhuangdao, Hebei 066004, People’s Republic of China
| | - Yuanfang Gong
- College of Animal Science and Technology, Hebei Normal University of Science and Technology, Qinhuangdao, Hebei 066004, People’s Republic of China
| | - Jingshi Li
- College of Animal Science and Technology, Agricultural University of Hebei Province, Baoding, Hebei 071001, People’s Republic of China
| | - Xianglong Li
- College of Animal Science and Technology, Hebei Normal University of Science and Technology, Qinhuangdao, Hebei 066004, People’s Republic of China
| |
Collapse
|
11
|
Chi-miR-3031 regulates beta-casein via the PI3K/AKT-mTOR signaling pathway in goat mammary epithelial cells (GMECs). BMC Vet Res 2018; 14:369. [PMID: 30482199 PMCID: PMC6258393 DOI: 10.1186/s12917-018-1695-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2018] [Accepted: 11/12/2018] [Indexed: 12/19/2022] Open
Abstract
BACKGROUND MicroRNAs can regulate gene expression at the posttranscriptional level through translational repression or target degradation. Our previous investigations examined the differential expression levels of chi-miR-3031 in caprine mammary gland tissues in colostrum and common milk stages. RESULTS The present study detected the role of chi-miR-3031 in the lactation mechanisms of GMECs. High-throughput sequencing was used to analyze transcriptomic landscapes of GMECs transfected with chi-miR-3031 mimics (MC) and a mimic negative control (NC). In the MC and NC groups, we acquired 39,793,503 and 36,531,517 uniquely mapped reads, respectively, accounting for 85.85 and 81.66% of total reads. In the MC group, 180 differentially expressed unigenes were downregulated, whereas 157 unigenes were upregulated. KEGG pathway analyses showed that the prolactin, TNF and ErbB signaling pathways, including TGFα, PIK3R3, IGF2, ELF5, IGFBP5 and LHβ genes, played important roles in mammary development and milk secretion. Results from transcriptome sequencing, real-time PCR and western blotting showed that chi-miR-3031 suppressed the expression of IGFBP5 mRNA and protein. The expression levels of β-casein significantly increased in the MC and siRNA-IGFBP5 groups. We observed that the down-regulation of IGFBP5 activated mTOR at the Ser2448 site in GMECs transfected with MC and siRNA-IGFBP5. Previous findings and our results showed that chi-miR-3031 activated the PI3K-AKT-mTOR pathway and increased β-casein expression by down-regulating IGFBP5. CONCLUSIONS These findings will afford valuable information for improving milk quality and contribute the development of potential methods for amending lactation performance.
Collapse
|